Clyde Tombaugh Interview (page: 3 / 8)

Clyde Tombaugh: You carry on through even despite of discouraging situations and you never lose sight of the goal. Often, you experience hardships involved like freezing in that cold dome at night, loss of sleep, and that gets pretty wicked, but I was interested in getting the results. It takes a dedication to achieve that kind of thing. A lot of people would give up and quit.

Clyde Tombaugh: When I was on the farm, we got hailed out. That meant total lack of money and I couldn't afford to go to college. This was a blow. I realized that I would have some very tough sledding, and I was very discouraged because I didn't see much hope of getting into the field I wanted to get into with no college education. I didn't know anybody particularly important in the field, so I felt I was under a great disadvantage and could hardly hope to do what I did.

How did you deal with that disappointment?

Clyde Tombaugh: It was depressing, very depressing. I worried about how I would make a living. I didn't want to stay on the farm. It didn't offer the challenge I wanted and yet, without a college education, I felt that I was really out of luck.

I just kept on studying and then the breaks came. I kept making telescopes and learning more about optics and that's the knowledge that paid off. I was really preparing myself for a better thing than I realized at the time.

Getting the invitation to go to Flagstaff was a real piece of luck, but the other was preparing myself. I think of the Chinese philosopher, Confucius. He said, "The future belongs to those who prepare for it," and I never forgot that.

So in your way, you were always preparing. Let's relive that experience of when you realized you had discovered a real planet.

Clyde Tombaugh: I was assigned to taking photographs at night with the telescope. It was a wide-angle photographic telescope with a one-hour exposure. I developed the plates and so on, and a few days later I'd put them on a special machine called the Blink-Comparator, where you compared two plates rapidly in alternating views, to see if any change occurred on the star field, from one plate to the other made a few nights later. That was the technique, because these plates would have several hundred thousand star images a piece. That's an awesome thing to look at and realize you had to see, out of all those images, which one moved. The challenge was far more difficult than most people ever realized.

I had some soul-searching questions for myself. Do I want to go through this very tedious job or not? I didn't want to go back to the farm to pitch hay, and I knew I had to do this job or go back to the farm. So I went through some pretty tedious hardship to accomplish this, but I was dedicated and I liked the work really, and I was very, very careful. All the suspects are checked with a third plate. I did the job very thoroughly, and it paid off. Now, I had figured out beforehand, if there was a Planet X, how I would recognize it if I encountered it. So I thought all this out beforehand.

What started you looking for this Planet X?

Clyde Tombaugh: Percival Lowell interpreted some of what they call residuals -- slight irregularities in the orbit of Uranus and Neptune -- as indicative of a mass out there as yet unseen. Like the case of Neptune being discovered mathematically before it was seen.

These residuals were so small that it was questionable whether they were real or not, but they were the best he had. He predicted that there was a planet out there about seven times more massive than the earth, beyond the orbit of Neptune. Of course, Pluto does not have that much mass.

Tell me about the day that you actually discovered the planet
Pluto.

Clyde Tombaugh: When I took the photographs, I had no idea that Pluto's image was on those plates, not until I began to scan them carefully some time later. In fact, it was several weeks later when I got to that pair. I had taken the plates of the telescope the previous month, in January, 1930.

I did not know that I had recorded the image of Pluto on those plates, not until I scanned them later in February. You passed your gaze over all these stars that you have to be conscious of seeing every star image, because you don't know which one's going to shift, if they shift. It's very tedious work and you go through tens of thousands of star images. I came to one place where it actually was, turned the next field and there it was! Instantly, I knew I had a planet beyond the orbit of Neptune because I knew the amount of shift was what fitted the situation. That was the most instantaneous thrill you can imagine. It just electrified me!

That was the 18th of February, 1930, about four o'clock in the afternoon. I realized in a few seconds' flash that I'd made a great discovery, that I'd become famous, and I didn't know what would happen after that. It was a very intense thrill. You don't have that kind of a thrill very often.

Bet you couldn't wait to tell someone.

Clyde Tombaugh: Well at first I had a little sense of caution. I thought I'd better check this third plate, which is another date, see if there's an image there in the right place that would be consistent with the images on the other plates. That was the final proof. Sure enough, it was there. That was when I was 100 percent sure.